It took 110 days for coronavirus infections in the country to reach one lakh, while just 39 days more to go past the five lakh-mark.
Medical experts have pointed to the ramped up COVID-19 testing, now available more extensively and at a reasonable price, as a big reason for the spike in cases recently.
Six days after recording four lakh infections, India's COVID-19 tally went past the five lakh-mark on Saturday with the highest single-day surge of 18,552 cases, while the death toll climbed to 15,685, according to Union health ministry data.
The COVID-19 caseload increased to 5,08,953, while 384 fatalities were recorded in the last 24 hours, the updated figure at 8 am showed.
This was the fourth consecutive day when coronavirus infection increased by more than 15,000, while there has been a surge of 3,18,418 infections from June 1 till 27. Maharashtra, Tamil Nadu, Delhi, Gujarat and Uttar Pradesh are the top contributors to the rising tally.
It took 64 days for COVID-19 cases in India to touch the (May 19) one lakh-mark from 100 cases, and another fortnight to cross two lakh cases on June 3. It took 10 days for the tally to touch the three lakh-mark and another eight days for the cases to climb to four lakh.
The nationwide lockdown was first imposed on March 25 for 21 days in a bid to contain the spread of the novel coronavirus. The lockdown was first extended till May 3 and then again till May 17. It was further extended till May 31.
The lockdown is now restricted only in containment zones across the country and will continue till June 30. A large number of social, economic, religious and sports activities are currently allowed to function under what the ministry of home affairs termed as 'Unlock 1'.
After the government initiated the unlock procedure to make-up for the economic cost of the lockdown, the COVID-19 cases started to gallop.
Dr Monica Mahajan, Director, Internal Medicine, Max Healthcare, said it is important to understand the reason for the exponential rise in cases.
The numbers are doubling at such a fast rate due to factors such as the high reproduction number of the virus (the number of cases, on average, an infected person will cause during their infectious period), she said. Also, with the lifting of lockdown norms people's behaviour has changed again as they are not acting as responsibly as before in terms of social distancing, and testing has become more liberal, said Mahajan.
She said the price of the test has come down and test kits are more easily available, so more cases are being detected.
Noted city-based lung surgeon Dr Arvind Kumar said definitely a big reason for cases going up is increased testing.
The percentage of people turning out to be positive from among those tested is also going up as due to lifting of the lockdown people have completely forgotten social distancing norms and are out on the streets with scant regard for the pandemic, said Kumar, who works at Sir Ganga Ram Hospital.
According to the Indian Council of Medical Research, a cumulative total of 79,96,707 samples have been tested up to June 26 with 2,20,479 samples being tested on Friday, the highest in a day since the beginning of the pandemic.
The government has ramped up its testing infrastructure across the country significantly with the ICMR validating around 1,007 diagnostic labs, of which 734 are in the government sector and 273 private sector.
The per day testing capacity which was around 1.4 lakh on May 25 has been increased to three lakh per day now.
Starting with one single laboratory, the National Institute of Virology in Pune and having 100 laboratories in the beginning of the lockdown, the ICMR on June 23 validated 1000th testing laboratory.
The real-time RT-PCR is the gold standard test for detecting cases of COVID-19 and the average time taken is around 4-5 hours from receipt of sample to getting the result. It requires a specialised laboratory set-up because of which this test cannot be performed at every district-level lab which does not have molecular virology facilities, the ICMR said recently.
Thus the TrueNat and the CBNAAT systems have also been deployed for diagnosis of COVID-19 in view of availability of customised cartridges.
Besides, the ICMR recently also approved the use of rapid-antigen test for coronavirus infection that gives results in 30 minutes and has also advised carrying out rapid antibody tests only for surveillance purposes.
India reported its first case of coronavirus infection on January 30 from Kerala. The number of active cases currently stands at 1,97,387 while 2,95,880 people have recovered and one patient has migrated.
"Thus, around 58.13 per cent patients have recovered so far," an official said.
India is the fourth worst-hit nation by the pandemic after the US, Brazil and Russia.
According to Johns Hopkins University, which has been compiling COVID-19 data from all over the world, India is at the eighth position in terms of the death toll.